Squash are promiscuous. They crossbreed like crazy, and hybrids that have gone to seed might also revert to a parent. If you seeded this yourself, you'd know, so I'm assuming this one came up on its own? I always have mystery squash in the garden, and I do have one that looks like yours, too. Last year, a very lusty butternut showed up in the corn rows and gave us dozens of squash without anyone ever planting a seed; these also happened to be true to type. You never know; maybe you have a brand new variety.

Sadly, while those cross-bred volunteer squash are often vigorous, they usually don't taste like much. I've often let them go ahead and grow, just because they're fun to watch. But then they end up in the compost.

This is called doodhi or ghia in Hindi, smooth light skin which can be easily peeled off. its used a lot in Indian cooking in stews & is a mainstay in making dumplings known as kofta.
Peel & dice the doodhi , about 2 cups, (check if it tastes bitter before you cook it), boil in 2 cups of water with a pinch of turmeric & salt. Make a gritty paste of 1/2 cup shredded coconut, 1-2 tsp cumin seeds 1 tsp rice flour and 1 deseeded jalapeno, add it to the boiled doodhi till it thickens. Heat 1 tbsp of canola in skillet till smoking, add a tsp of black mustard seeds, 1 arbol chile & a sprigs worth of curry leaves, when the mustard pops add to the stew, Stir & serve with rice.